We have a domain ID that was created under a particular name and then renamed in AD under the same SID. Occasionally SQL starts to resolve login attempts under the old name instead on the new name. So application login attempts fail. I can verify this is happening by doing the following...

1. Open the new login dialog box and click on search.2. Type in Domain\NewDomainName and click on Check Names.3. The correct ID (the new name) is displayed.4) Click OK5) The incorrect ID (the old name) is displayed.

If I then type in the correct ID name and click OK, the correct new name is added to the login list. The login attempt to the application is then successful.

The problem is resolved for several days and then it reoccurs.

The current suggestion in my group is to reboot the boxes, but I can't get downtime for a couple of weeks. The environment is a 3+1 cluster on 4 64-bit boxes.